What is CVE-2026-5466?

CVE-2026-5466 is a high-severity vulnerability in Wolfssl, classified under Improper Verification of Cryptographic Signature. CVSS score: 8.1/10. Published 2026-04-10.

How severe is CVE-2026-5466?

High severity. CVSS v3 base score is 8.1 out of 10.

Vulnerability in Wolfssl

CVE-2026-5466

wolfSSL's ECCSI signature verifier `wc_VerifyEccsiHash` decodes the `r` and `s` scalars from the signature blob via `mp_read_unsigned_bin` with no check that they lie in `[1, q-1]`. A crafted forged signature could verify against any messa…

EPSS: 0.000 (0.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.

Affected products

Wolfssl — versions 0

Weakness classification (CWE)

CWE-347 — Improper Verification of Cryptographic Signature

References

facts@wolfssl.com (Issue Tracking)

Frequently asked questions

What is CVE-2026-5466?: CVE-2026-5466 is a high-severity vulnerability in Wolfssl, classified under Improper Verification of Cryptographic Signature. CVSS score: 8.1/10. Published 2026-04-10.
How severe is CVE-2026-5466?: High severity. CVSS v3 base score is 8.1 out of 10.